Usage monitoring control for mobile networks

ABSTRACT

In general, techniques are described for facilitating usage monitoring control in mobile networks. A mobile gateway comprising one or more processors and a memory may be configured to perform the techniques. The one or more processors may be configured to transmit a usage monitoring report indicative of usage of a service provided via a session for which usage monitoring was previously activated. The memory may be configured to store a monitoring key that was configured as a result of activating the usage monitoring for the service. The one or more processors may also be configured to, in response to the indication to deactivate the usage monitoring, remove the monitoring key that was configured as a part of activating the usage monitoring for the session.

TECHNICAL FIELD

This disclosure relates to computer networks and, more specifically, tousage monitoring control for mobile networks.

BACKGROUND

A cellular radio access network is a collection of cells that eachincludes at least one base station capable of transmitting and relayingsignals to subscribers' wireless devices. A “cell” generally denotes adistinct area of a mobile network that utilizes a particular frequencyor range of frequencies for transmission of data. A typical base stationis a tower to which are affixed a number of antennas that transmit andreceive the data over the particular frequency. Wireless devices, suchas cellular or mobile phones, smart phones, camera phones, personaldigital assistants (PDAs) and laptop computers, may initiate orotherwise transmit a signal at the designated frequency to the basestation to initiate a call or data session and begin transmitting data.

Mobile networks convert cellular signals, e.g., Time Division MultipleAccess (TDMA) signals, Orthogonal Frequency-Division Multiplexing (OFDM)signals or Code Division Multiple Access (CDMA) signals, received at abase station from wireless devices into Internet protocol (IP) packetsfor transmission within packet-based networks. A number of standardshave been proposed to facilitate this conversion and transmission ofcellular signals to IP packets, such as a general packet radio service(GPRS) standardized by the Global System for Mobile Communications (GSM)Association, an evolution of UMTS referred to as Long Term Evolution(LTE), mobile IP standardized by the Internet Engineering Task Force(IETF), as well as other standards proposed by the 3^(rd) GenerationPartnership Project (3GPP), 3^(rd) Generation Partnership Project 2(3GGP/2) and the Worldwide Interoperability for Microwave Access (WiMAX)forum.

A typical mobile service provider network, or “mobile network,” includesa core packet-switched network, a transport network, and one or moreradio access networks. The core packet-switched network for the mobilenetwork establishes logical connections, known as bearers, among themany service nodes on a path between a wireless device, attached to oneof the radio access networks, and a packet data network (PDN). Theservice nodes then utilize the bearers to transport subscriber trafficexchanged between the wireless device and the PDN, which may include,for example, the Internet, an enterprise intranet, a layer 3 VPN, and aservice provider's private network. Various PDNs provide a variety ofpacket-based data services to wireless devices to enable the wirelessdevices to exchange service data with application or other servers ofthe PDNs. In addition, while primarily described with respect to serviceproviders and mobile service provider networks, a mobile network may bedeployed by many different types of entities, including enterprises andgovernment agencies. Accordingly, the term “mobile network” may be usedherein to encompass many different types of cellular networkarchitectures and operators.

Mobile networks perform detailed and accurate monitoring of serviceusage so that proper charging information can be generated forpotentially millions of customers in order to provide revenue for theservice providers. In general, there are three distinct aspects to theprocess that translates service use into a bill for services—charging,rating and billing. Charging gathers statistics regarding service usagefor each customer. Rating is the process of determining how much eachservice used costs each particular customer according to the servicecontract. Billing is the process of generated a customer's invoice forservices.

The mobile network gateway anchors subscriber sessions and executesnetwork access control functions including charging control (also knownas Policy and Charging Enforcement Function for 3GPP networks or theinitialism PCEF), which refers to the process of associating packetsthat belong to a service data flow to a charging key and applying onlinecharging and/or offline charging, as appropriate (where a charging keyincludes information used by the charging online and offline chargingservers for rating purposes). Accordingly, the mobile network gatewaycollects charging information related to the external data network usageand to network resource usage, such as the amount of data categorized byquality of service (QoS), the user protocols, and the usage of thepacket data protocol (PDP) address.

A mobile network gateway typically cooperates with online and offlinecharging server to perform the charging and rating processes in order togenerate the charging information. In general, offline charging denotesa charging mechanism in which charging information does not affect, inreal-time, the service(s) rendered. The network reports resource usageto the billing domains after the resource usage has occurred. Bycontrast, online charging can affect, in real-time, the service(s)rendered and therefore requires a direct interaction between the mobilenetwork gateway and the online charging server for subscriber sessionand/or service(s) control. An online charging server typically maintainssubscriber accounts that may be queried prior to granting permission touse requested network resources.

In the 3GPP TS 29.212 standard, there are a number of different ways bywhich to activate or otherwise enable usage monitoring for purposes ofpolicy and charging control. Likewise, the 3GPP TS 29.212 standardprovides a number of different ways by which to deactivate or otherwisedisable usage monitoring. Additional information regarding chargingcontrol and management is found in “3GPP TS 29.212,” 3^(rd) GenerationPartnership Project, Technical Specification Group Core Network andTerminals, Policy and Charging Control (PCC); Reference points (Release12), December, 2013; “3GPP TS 32.299,” 3^(rd) Generation PartnershipProject, Technical Specification Group Services and System Aspects,Diameter charging applications (Release 11), December, 2012; “3GPP TS32.240,” 3^(rd) Generation Partnership Project, Technical SpecificationGroup Services and System Aspects, Charging architecture and principles(Release 12), March, 2013; and “Diameter Credit-Control Application,”Request for Comments 4006, Internet Engineering Task Force, NetworkWorking Group, August 2005; each of which being incorporated byreference in its entirety herein. However, discrepancies exist invarious usage monitoring activation and deactivation scenarios that mayresult in mobile session disruptions and/or inaccurate usage monitoring.

SUMMARY

In general, techniques are described for usage monitoring control in thecontext of mobile or wireless access networks. The techniques may enablea network device, such as a router operating as a packet data network(PDN) gateway (PGW) within a 3GPP-compliant mobile access network, toovercome a number of discrepancies that arise when configuring usagemonitoring with respect to a session between a mobile or wireless deviceand the mobile access network to access one or more services. Forexample, in activating usage monitoring, a policy and charging rulesfunction (PCRF) may provide incomplete activation information. Ratherthan discard this incomplete activation information, the PGW mayconfigure but not activate usage monitoring for the session in the eventinformation sufficient to complete the incomplete activation informationis forthcoming.

As another example, in deactivating usage monitoring, a PCRF maydeactivate usage monitoring in response to a usage report from the PGWproviding the usage information. In this situation, rather than ignorethe deactivation and continue to report usage information, the PGW maydisable usage monitoring for the session without, as is common to the3GPP specification, providing a usage report.

As yet another example, in installing a policy and charging control(PCC) rule, the PCRF may provide incomplete information to activateusage monitoring. Rather than install the rule without usage monitoringdespite the discrepancy as to whether usage monitoring was intended tobe activated or not, the PGW may reject the PCC rule while also possiblyproviding a result_code to enable the PCRF to evaluate the reason forwhich the rule was rejected. As such the foregoing techniques mayovercome many ambiguities and discrepancies in PCRF/PGW interactionsthat may facilitate better operation of mobile access networks.

In one aspect, a method comprises establishing, by a mobile gatewaypositioned within a mobile access network, a session by which a mobiledevice accesses a service provided by the mobile access network, and inresponse to receiving an incomplete indication to activate usagemonitoring of the service using the session, configuring at least aportion of the usage monitoring by the mobile gateway without activatingthe usage monitoring.

In another aspect, a mobile gateway comprises one or more processorsconfigured to establish a session by which a mobile device accesses aservice provided by a mobile access network, and in response toreceiving an incomplete indication to activate usage monitoring of theservice using the session, configuring at least a portion of the usagemonitoring without activating the usage monitoring, and a memoryconfigured to store the usage monitoring configuration.

In another aspect, a system comprises a mobile device, and a mobilegateway positioned in a mobile access network. The mobile gatewaycomprises one or more processors configured to establish a session bywhich a mobile device accesses a service provided by a mobile accessnetwork, and in response to receiving an incomplete indication toactivate usage monitoring of the service using the session, configuringat least a portion of the usage monitoring without activating the usagemonitoring, and a memory configured to store the usage monitoringconfiguration.

In another aspect, a non-transitory computer-readable storage medium hasstored thereon instructions that, when executed, cause one or moreprocessors of a mobile gateway to establish a session by which a mobiledevice accesses a service provided by a mobile access network in whichthe mobile gateway is positioned, and in response to receiving anincomplete indication to activate usage monitoring of the service usingthe session, configure at least a portion of the usage monitoring by themobile gateway without activating the usage monitoring.

In another aspect, a method comprises transmitting, by a mobile gatewaypositioned within a mobile access network, a usage monitoring reportindicative of usage by a mobile device of a service provided over asession for which usage monitoring was previously activated, receiving,by the mobile gateway and in response to transmitting the usagemonitoring report, an indication to deactivate usage monitoring of theservice for the session, and in response to the indication to deactivatethe usage monitoring, removing a monitoring key that was configured as apart of activating the usage monitoring of the service for the session.

In another aspect, a mobile gateway comprises one or more processorsconfigured to transmit a usage monitoring report indicative of usage bya mobile device of a service provided over a session for which usagemonitoring was previously activated, and a memory configured to store amonitoring key that was configured as a result of activating the usagemonitoring for the service. The one or more processors are alsoconfigured to receive, in response to transmitting the usage monitoringreport, an indication to deactivate usage monitoring of the service forthe session, and remove, in response to receiving an indication todeactivate the usage monitoring of the service for the session, themonitoring key that was configured as a part of activating the usagemonitoring of the service for the session.

In another aspect, a system comprises a device that performs a policyand charging rules function, a mobile device, and a mobile gatewaypositioned in a mobile access network. The mobile gateway comprises oneor more processors configured to transmit a usage monitoring reportindicative of usage by a mobile device of a service provided over asession for which usage monitoring was previously activated, and amemory configured to store a monitoring key that was configured as aresult of activating the usage monitoring for the service. The one ormore processors are also configured to receive, in response totransmitting the usage monitoring report, an indication to deactivateusage monitoring of the service for the session, and remove, in responseto receiving an indication to deactivate the usage monitoring of theservice for the session, the monitoring key that was configured as apart of activating the usage monitoring of the service for the session.

In another aspect, a non-transitory computer-readable storage medium hasstored thereon instructions that, when executed, cause one or moreprocessors of a mobile gateway to transmit a usage monitoring reportindicative of usage by a mobile device of a service provided over asession for which usage monitoring was previously activated, receive, inresponse to transmitting the usage monitoring report, an indication todeactivate usage monitoring of the service for the session, and inresponse to the indication to deactivate the usage monitoring, remove amonitoring key that was configured as a part of activating the usagemonitoring of the service for the session.

In another aspect, a method comprises establishing, with a mobilegateway positioned in a mobile access network, a session by which amobile device is to access a service, and in response to receiving anindication to activate a charging rule having an incomplete indicationto activate usage monitoring with respect to the service provided viathe session, rejecting the charging rule.

In another aspect, a mobile gateway comprises one or more processorsconfigured to establish a session by which a mobile device is to accessa service, and in response to receiving an indication to activate acharging rule having an incomplete indication to activate usagemonitoring with respect to the service provided via the session,rejecting the charging rule.

In another aspect, a system comprises a mobile device, and a mobilegateway positioned in a mobile access network. The mobile gatewaycomprises one or more processors configured to establish a session bywhich the mobile device is to access a service, and in response toreceiving an indication to activate a charging rule having an incompleteindication to activate usage monitoring with respect to the serviceprovided via the session, reject the charging rule.

In another aspect, a non-transitory computer-readable storage medium hasstored thereon instructions that, when executed, cause one or moreprocessors of a mobile gateway to establish a session by which a mobiledevice is to access a service, and in response to receiving anindication to activate a charging rule having an incomplete indicationto activate usage monitoring with respect to the service provided viathe session, reject the charging rule.

The details of one or more embodiments of the techniques are set forthin the accompanying drawings and the description below. Other features,objects, and advantages of the techniques will be apparent from thedescription and drawings, and from the claims.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram illustrating an example network system thatperforms fine-grained charging control at the rating group level formulti-service subscriber sessions according to techniques described inthis disclosure.

FIG. 2 is a block diagram illustrating an example network system thatperforms the usage monitoring control techniques described in thisdisclosure.

FIG. 3 is a block diagram illustrating an example mobile network gatewaythat performs the usage monitoring control techniques described in thisdisclosure.

FIGS. 4-6 are flowcharts illustrating exemplary operations of a mobilegateway in performing various aspects of the usage monitoring controltechniques described in this disclosure.

FIG. 7 is a block diagram illustrating another example network systemthat performs the usage monitoring control techniques described in thisdisclosure.

Like reference characters denote like elements throughout the figuresand text.

DETAILED DESCRIPTION

FIG. 1 is a block diagram illustrating an example network system thatperforms usage monitoring control according to techniques described inthis disclosure. In this example, network system 2 includes packet datanetwork (PDN) 12 coupled to mobile service provider network 4 (“mobilenetwork 4”) via gateway 8 of mobile network 4. Packet data network 12supports one or more packet-based services that are available forrequest and use by wireless device 6. As examples, PDN 12 may provide,for example, bulk data delivery, voice over Internet protocol (VoIP),Internet Protocol television (IPTV), Short Messaging Service (SMS),Wireless Application Protocol (WAP) service, Session Initiation Protocol(SIP) services, or customer-specific application services. Packet datanetwork 12 may comprise, for instance, a local area network (LAN), awide area network (WAN), the Internet, a virtual LAN (VLAN), anenterprise LAN, a layer 3 virtual private network (VPN), an InternetProtocol (IP) intranet operated by the mobile service provider thatoperates mobile network 4, an enterprise IP network, or some combinationthereof. In various instances, PDN 12 is connected to a public WAN, theInternet, or to other networks. Packet data network 12 executes one ormore packet data protocols (PDPs), such as IP (IPv4 and/or IPv6), X.25or Point-to-Point Protocol (PPP), to enable packet-based transport ofPDN 12 services.

Wireless device 6 is a wireless computing device that may represent, forexample, a mobile telephone, a laptop or desktop computer having, e.g.,a 3G/4G wireless card or hub, wireless-capable netbook, video gamedevice, pager, smart phone, a personal data assistant, or anycombination of these items. Wireless device 6 may run one or moreapplications, such as VoIP clients, video games, videoconferencing,E-mail, and Internet browsers, among others. Certain applicationsrunning on wireless device 6 may require access to services offered byPDN 12. Wireless device 6 may also be referred to, in variousarchitectural embodiments for example, as User Equipment (UE), a MobileStation (MS), a subscriber device, or a mobile device.

A mobile service provider operates mobile network 4 to provide networkaccess, data transport and other services to wireless device 6. Ingeneral, mobile network 4 may implement any commonly defined cellularnetwork architecture including those defined by standards bodies, suchas a Global System for Mobile communication (GSM) Association, a 3^(rd)Generation Partnership Project (3GPP), a 3^(rd) Generation PartnershipProject 2 (3GGP/2), an Internet Engineering Task Force (IETF) and aWorldwide Interoperability for Microwave Access (WiMAX) forum. Forexample, mobile network 4 may implement one or more of a GSMarchitecture, a General Packet Radio Service (GPRS) architecture, aUniversal Mobile Telecommunications System (UMTS) architecture, and anevolution of UMTS referred to as Long Term Evolution (LTE), each ofwhich are standardized by 3GGP. Mobile network 4 may, alternatively orin conjunction with one of the above, implement a code division multipleaccess-2000 (“CDMA2000”) architecture. Mobile network 4 may, again as analternative or in conjunction with one or more of the above, implement aWiMAX architecture defined by the WiMAX forum.

Mobile network 4 may include a core packet-switched network (not shownin FIG. 1) and one or more radio access networks (also not shown in FIG.1). A core packet-switched network of mobile network 4 may comprise, forexample, a GPRS core packet-switched network, an IP-based mobilemultimedia core network, or an Evolved Packet Core (EPC). Wirelessdevice 6 communicates with mobile network 4 using a wirelesscommunication link to one of the radio access networks of the mobilenetwork. Radio access networks of mobile network 4 may include, forexample, for example, a GSM Radio Access Network (GRAN), a WiMAX radioaccess network, a UMTS Radio Access Network (UTRAN), and/or an evolutionof a UTRAN known as an E-UTRAN. Mobile network 4 may further include abackhaul or transport network (not shown) that includes land-basedtransmission lines, frequently leased by a service provider for themobile network, to transport user and control traffic between wirelessdevice 6 and gateway 8. The backhaul network also includes networkdevices such as aggregation devices and routers.

Gateway 8 is a network device that operates as a gateway to PDN 12 andmay represent, for example, a Gateway GPRS Serving Node (GGSN), anAccess Gateway (aGW), a Packet Gateway (P-GW), or any combination of theabove. Gateway 8 may comprise a router. While described herein withrespect to one or more particular architectures for ease of illustrationpurposes, mobile network 4 may implement any architecture includingthose set forth by any standards body and those proprietarily owned.Moreover, the techniques may apply to any mobile data protocol supportedby these architectures. The techniques therefore should not be limitedto cellular architectures referenced to herein and the mobile dataprotocols supported by these architectures. Gateway 8 and other elementsof mobile network 4 may, therefore, each represent an abstraction ofdevices found within any type of mobile network architectures.

Mobile network 4 establishes and operates bearers to transport usertraffic, in the form of PDP packet data units (PDUs), referred tohereinafter as “packets.” In general, a bearer is a set of networkresources and data transport functions in mobile network 4 to deliveruser traffic between two network entities. A bearer may include a path,a logical connection, or a physical or wireless connection between twonetwork devices. A bearer may comprise, for example, an Evolved PacketSystem (EPS) bearer. Further details regarding bearer setup andmanagement are found in “3GPP TS 23.401—General Packet Radio Service(GPRS) enhancements for Evolved Universal Terrestrial Radio AccessNetwork,” version 10.0.0, 3rd Generation Partnership Project, TechnicalSpecification Group Services and System Aspects, June 2010, and 3GPP TS36.300—Evolved Universal Terrestrial Radio Access (E-UTRA) and EvolvedUniversal Terrestrial Radio Access Network Evolved Universal TerrestrialRadio Access Network (E-UTRAN) Overall Description,” Release 10, 3rdGeneration Partnership Project, Technical Specification Group RadioAccess Network, 2010, the entire contents of each being incorporatedherein by reference.

Wireless device 6 attaches to mobile network 4, which establishes asubscriber session typically including a default bearer to carry usertraffic for the wireless device as part of an attach procedure. Thesubscriber session is an association between mobile network 4 andwireless device 6 that is identifiable by a combination of a wirelessdevice 6 PDP address and an Access Point Name (APN) or other PDNidentifier for PDN 12. In instances of mobile service provider network 4that include an IP-based connectivity access network (IP-CAN), asubscriber session represents an IP-CAN session. A subscriber sessionmay represent and alternatively be referred to as a PDP context.

Besides establishing a default bearer, the attach procedure may triggerestablishment, by mobile network 4, of one or more dedicated bearersbetween gateway 8 and wireless device 6 to carry user traffic for thesubscriber session. Dedicated bearers operate according to a differentset of quality of service (QoS) parameters and thus provide QoSdifferentiation to packet flows of various services engaged by wirelessdevice 6. For example, various dedicated bearers may provide differentguaranteed bit rates (GBR bearers) (or may not provide a guaranteed bitrate), maximum bit rates (MBRs), priority, packet delay budget, packeterror loss rate, and allocation and retention priority (ARP)characteristics. A particular bearer may transport packet flows formultiple services of a subscriber session when the QoS characteristicsof the bearer match the requirements of the services.

Gateway 8 includes monitoring client 10 that implements charging controlfor mobile network 4. Monitoring client 10 may, for instance, implementa Policy and Charging Enforcement Function (PCEF), which providesservice data flow detection, user plane traffic handling, triggeringcontrol plane session management in some instances, QoS handling, andservice data flow measurement as well as online and offline charginginteractions with online charging server 14 and offline charging server15. In some examples, monitoring client 10 provides policy and chargingcontrol (PCC) functionality. In such examples, an operator and/or anexternal entity, such as a Policy and Charging Rules Function (PCRF)entity (not shown in FIG. 1), provisions monitoring client 10 with oneor more PCC rules that each specify a set of information enabling thedetection of a service data flow and providing policy control and/orcharging control parameters. Monitoring client 10 then enforces serviceflow-based policy and charging control according to the PCC rules.Further example details regarding policy and charging control are foundin “3GPP TS 23.203,” incorporated above, as well as in U.S. patentapplication Ser. No. 12/947,463, filed Nov. 16, 2010, which isincorporated by reference herein in its entirety.

To facilitate offline charging, gateway 8 exchanges communications withoffline charging server 15 by interface 17, which may implement a Gareference point and may include a communication link. With offlinecharging, offline charging server 15 collects charging information fornetwork resource usage from gateway 8 and, in some cases, other elementsof mobile service provider network 4 concurrently with that resourceusage. In this sense, gateway 8 (more particularly monitoring client 10)may provide an offline charging data function (CDF) for network system 2and offline charging server 15 may provide a charging gateway function(CGF).

To facilitate online charging, gateway 8 exchanges communications withonline charging server 14 by interface 19, which may implement a Gy/Roreference point and may include a communication link. Online chargingserver 14 may include a Remote Authentication Dial-In User Service(RADIUS) server and may provide real-time credit control by performingtransaction handling, rating, and online correlation and management ofsubscriber accounts for mobile network 4. For example, monitoring client10 collects charging information, e.g., chargeable events and requestednetwork resource usage, and forwards the charging information to onlinecharging server 14 providing the online charging function (OCF) in orderto obtain authorization to provide the requested resources or chargeableevents. In this way, monitoring client 10 may provide an online chargingtrigger function (OTF). Additional details regarding online and offlinecharging may be found in TS 32.240 and TS 32.299, each of which isincorporated by reference, as noted above, in their respectiveentireties.

In the example of FIG. 1, mobile service provider network 4 establishesbearer 11 for a subscriber session for wireless device 6. Bearer 11 mayrepresent a default or dedicated bearer. Mobile service provider network4 maps packets associated with any of multiple services 13A-13C(collectively, “services 13”) to bearer 11, which mobile serviceprovider network 4 uses to transport the mapped packets in the downlinkdirection from gateway 8 toward wireless device 6 and in the uplinkdirection from wireless device 6 to gateway 8. Each of services 13 mayrepresent, e.g., conversation voice or video, real-time gaming, bufferedstreaming, Transmission Control Protocol (TCP)-based services (such asInternet access, HTTP-service, e-mail, chat, File Transfer Protocol(FTP), and Peer-to-Peer (P2P) services), IP Multimedia Subsystem (IMS)signaling, and so forth. Packets associated with service 13A may, forexample, constitute one or more packet flows that match a service dataflow (SDF) filter of an SDF template for the service.

Within the context of policy and charging control resides usagemonitoring in which, as one example, the PCRF may indicate, via the Gxreference point, that monitoring control is required for the accumulatedusage of network resources on a session-by-session basis. Usage may bedefined as volume or time of user plane traffic. Monitoring of bothtraffic volume and traffic time may occur concurrent to one another. Insome instances, the data collection for usage monitoring control isperformed per monitoring key, where a monitoring key may be defined fora single service data flow, a set of service data flows, or for all thetraffic in a session.

In other words, the PCRF may apply usage monitoring for the accumulatedusage of network resources on a CAN session and user basis. Usagemonitoring may be required of reinforcing dynamic policy decisions basedon the total network usage in real-time. The PCRF that uses usagemonitoring for making dynamic policy decisions may set and send theapplicable thresholds to monitoring client 10, which may represent oneor both of the PCEF and a traffic detection function (TDF). Monitoringclient 10 may, more generally, represent any unit configured to monitorusage and notify the PCRF when a threshold (defined, as one example, interms of volume) is reached and report the accumulated usage since thelast report for usage monitoring.

The PCRF may enable usage monitoring in a number of ways. Whenestablishing an IP-CAN session, the PCRF may enable usage monitoring inresponse to an initial credit control request (CCR-I) message frommonitoring client 10 by sending an initial credit control answer (CCA-I)message that specifies the monitoring key for each data set (which mayrefer to a portion of a session that delivers a particular service) forwhich the PCRF wants to enable usage monitoring. The PCRF may providethe monitoring key in a Monitoring-Key attribute-value pair (AVP) for aparticular PCC rule to enable usage monitoring for the correspondingservice to which the PCC rule applies. The PCC rule, in other words, mayinclude service data flow (SDF) information that allows foridentification of IP traffic, charging parameters used to charge thistraffic, and quality of service (QoS) parameters to be applied to thetraffic that the SDF filters identify. The Monitoring-Key AVP mayidentify this PCC rule, thereby informing monitoring client 10 that theusage monitoring has been enabled for the corresponding SDF filters. Insome instances, the PCRF may enable usage monitoring for the entiresession (and not just a service provided via the session or a portion ofthe session) by sending this CCA-I without the Monitoring-Key AVP.

The PCRF may request that monitoring client 10 report usage by includinga Usage-Monitoring-Report AVP (in the Usage-Monitoring-Information AVP)having a value set to “USAGE_MONITORING_REPORT_REQUIRED” in the CCA-Umessage. The PCRF may indicate that the PCC rules are to be installed bysending a Charging-Rule-Install AVP. The Charging-Rule-Name AVP and aMonitoring-Key AVP that corresponds to the monitoring key are specifiedin the Usage-Monitoring-Information AVP.

The PCRF may further install rules using a re-authorization request(RAR) message and request usage monitoring for those rules. These PCCrules may be statically defined at monitoring client 10 or dynamicallydefined and provided to monitoring client 10. In any event, the RARmessage may include, when monitoring is requested for a PCC rule, aUsage-Monitoring-Information AVP for each monitoring key, and thedesired threshold levels (for specifying when to report usageinformation, as discussed in more detail below) may be provided in aGranted-Service-Unit AVP. The RAR Usage-Monitoring-Information AVP mayinclude a Monitoring-Key AVP specifying the monitoring key associatedwith the PCC rule being installed and the Granted-Service-Unit AVP witha CC-Total-Octets AVP stating the total number of requested, granted orused octets regardless of direction, a CC-Input-Octets AVP stating thenumber of requested, ranged or used octets that can be/have beenreceived from the end user, a CC-Output-Octets AVP providing a number ofrequested, granted or used octets that can be/have been sent to the enduser, a Usage-Monitoring-Level AVP set to “PCC-RULE_LEVEL.” As with theCCA-I message above, the PCRF may indicate that the PCC rule is to beinstalled by sending a Charging-Rule-Install AVP that includes aCharging-Rule-Name AVP and a Monitoring-Key AVP that corresponds to themonitoring key specified in the Usage-Monitoring-Information AVP.

The PCRF may also remove PCC rules for which usage monitoring may havebeen enabled. A PCC rule installed via the RAR/RAA (re-authorizationanswer) message exchange may also be removed, which may trigger anupdate request from monitoring client 10 that involves monitoring client10 reporting the accumulated usage information. In other words, when thePCRF removes a rule via a RAR message, the PCRF is also disabling anyusage monitoring associated with that rule. Monitoring client 10 maysend an update CCR (CCR-U) message with a CC-Request-Type AVP set to“UPDATE REQUEST” and an Event-Trigger AVP set to “USAGE_REPORT” toreport accumulated usage for the now disabled one or more usagemonitoring keys.

The PCRF may, in other words, configure an Event Reporting Function(ERF) executed by monitoring client 10 using such Event-Triggers. TheERF performs event trigger detection. When an event matching the eventtrigger occurs the ERF reports the occurred event to the PCRF. The eventtriggers define the conditions when the ERF is to interact again withthe PCRF after IP-CAN session establishment. The PCRF may subscribe tosome event triggers (e.g., those that are not necessarily required forproper delivery and maintenance of services). While the foregoing relateto installing an Event-Trigger AVP to configure usage monitoring uponreaching some event trigger, monitoring client 10 may send updaterequests via CCR-U/CCA-U message exchanges independent of usagemonitoring and reporting.

Additionally, when an IP-CAN session is terminated, monitoring client 10may report accumulated usage for a specific monitoring key by sending atermination CCR (CCR-T) message. The CCR-T message may include theUsage-Monitoring-Information AVP that includes a Monitoring-Key AVP andthe accumulated usage since the last report in the form of aUsed-Service-Unit AVP that includes a CC-Total-Octets AVP, aCC-Input-Octets AVP and a CC-Output-Octets AVP.

In some instances, the PCRF may provide the Usage-Monitoring-InformationAVP along with an Event-Trigger AVP having the value set to“USAGE_REPORT” when the PCRF is not currently subscribed to this“USAGE_REPORT” Event-Trigger AVP. When the Event-Trigger AVP having avalue set to “USAGE_REPORT” has already been sent or provided to themonitoring client 10 (or, in other words, when the PCRF has previouslysubscribed to the “USAGE_REPORT” Event-Trigger for the current session),the PCRF may send only the Usage-Monitoring-Information AVP withoutincluding the Event-Trigger AVP having the value set to “USAGE_REPORT.”

Moreover, although described above as explicitly indicating when usagemonitoring is to be enabled, the PCRF may also install PCC rules thatactivate or otherwise enable usage monitoring. That is, the PCRF maydynamically create and then send a Charging-Rule-Definition AVP tomonitoring client 10 that includes a Monitoring-Key AVP along with theUsage-Monitoring-Information AVP as described above. Monitoring client10 may then install this dynamically created PCC rule. In otherinstances, monitoring client 10 may be statically configured with PCCrules and the PCRF may indicate that one or more of these staticallyconfigured rules are to be installed. In the context of usagemonitoring, the PCRF may send a Charging-Rule-Install AVP to install apredefined rule, where this predefined rule is configured with aMonitoring-Key AVP and the corresponding Usage-Monitoring-InformationAVP. Monitoring client 10 may, in response to receiving thisCharging-Rule-Install AVP, install the rule and thereby activate usagemonitoring.

Once usage monitoring is enabled, the PCRF may explicitly disable usagemonitoring as a result of receiving a credit control request (CCR) fromthe traffic detection function (as, for example, executed by gateway 8within or separate from monitoring client 10 but not explicitly shown inFIG. 1 for ease of illustration purposes), where the CCR is not relatedto reporting usage, but related to other external triggers (e.g., asubscriber profile update). CCR messages, CCA messages, RAR messages andRAA messages are described in more detail in a request for comments(RFC) 4006, entitled “Diameter Credit-Control Application,” dated August2005, and available at: http://www.ietf.org/rfc/rfc4006.txt, the entirecontents of which are hereby incorporated by reference as if set forthfully herein. The PCRF may also explicitly disable usage monitoring inresponse to an internal trigger. To disable monitoring for a monitoringkey, the PCRF may send the Usage-Monitoring-Information AVP includingonly the applicable monitoring key within the Monitoring-Key AVP and theusage-Monitoring-Support AVP set to “USAGE_MONITORING_DISABLED.”

In this respect, the 3GPP TS 29.212 standard provides for a number ofdifferent ways by which to activate or otherwise enable usage monitoringfor purposes of policy and charging control. Likewise, the 3GPP TS29.212 standard provides a number of different ways by which todeactivate or otherwise disable usage monitoring. However, discrepanciesexist in various usage monitoring activation and deactivation scenariosthat may result in mobile session disruptions and/or inaccurate usagemonitoring.

For example, the 3GPP TS 29.212 standard does not address variousinstances where the PCRF or operator provides an incomplete indicationto activate usage monitoring with respect to a service provided via asession (e.g., one of services 13) to monitoring client 10. Toillustrate, the 3GPP TS 29.212 standard does not specify during non-PCCrule-based activation of usage monitoring how monitoring client 10 is tooperate when the PCRF sends a Usage-Monitoring-Information AVP toactivate usage monitoring for a service (identified via a SDF) providedvia a session in which an Event-Trigger AVP having a value set to“USAGE_REPORT” has not previously been established for this SDF or sentalong with the Usage-Monitoring-Information AVP. In this respect, theindication to activate usage monitoring is incomplete, given that theappropriate Event-Trigger AVP has not been specified.

As another illustration, the 3GPP TS 29.212 standard does not define howmonitoring client 10 is to operate when the PCRF attempts to install adynamic rule via a Charging-Rule-Definition AVP accompanied by aMonitoring-Key AVP within monitoring client 10 in the case where aUsage-Monitoring-Information AVP has not been previously defined for theservice provided via the session to be monitored or provided along withthe Monitoring-Key AVP and Charging-Rule-Definition AVP. Again, theindication to activate usage monitoring is incomplete. This sameincomplete indication to activate usage monitoring also extends to thecontext of the pre-defined rule, where rules are statically definedwithin monitoring client 10 and then installed per an indication fromthe PCRF. In other words, the 3GPP TS 29.212 standard does not definehow monitoring client 10 is to operate when the PCRF sends aCharging-Rule-Install AVP for a predefined rule which is configured witha Monitoring-Key AVP but not with the Usage-Monitoring-Information AVP.

The foregoing instances relate to usage monitoring activation, butsimilar discrepancies may exist in the context of usage monitoringdeactivation. For example, while the 3GPP TS 29.212 standard defines howthe PCRF and monitoring client 10 are to operate when disabling usagemonitoring in response to monitoring client 10 sending a CCR not relatedto usage reporting, the 3GPP TS 29.212 standard does not specify howmonitoring client 10 is to operate when monitoring client 10 sends a CCRrelated to usage reporting and the PCRF responds to this CCR related tousage reporting with an indication to disable usage reporting (or, morespecifically, a Monitoring-Key AVP associated with the service providedvia the session for which the CCR was reporting usage). All of theforegoing discrepancies may lead to mobile session disruptions and/orinaccurate usage monitoring given that different monitoring clients mayoperate in unpredictable ways that cause these disruptions or monitoringinaccuracies.

In accordance with various techniques of this disclosure, monitoringclient 10 may establish a session, e.g., one of sessions 13, by whichmobile device 6 is to access a service. In response to receiving anincomplete indication to activate usage monitoring with respect to theservice provided via the session, monitoring client 10 may configure theusage monitoring without activating the usage monitoring. In otherwords, when monitoring client 10 receives only aUsage-Monitoring-Information AVP (in a CCA/RAR) on a session which hadpotentially never received an Event-Trigger AVP set to “USAGE_REPORT”(including in this current message), then monitoring client 10 may storethe received Usage-Monitoring-Information (UMI) AVP, but will notactivate the received Usage-Monitoring-Information AVP. In thisinstance, it may be assumed that the PCRF is aware that if it sends theUMI AVPs without corresponding Event-Trigger AVPs, monitoring client 10will likely not perform any usage monitoring. If at any time monitoringclient 10 receives an Event-trigger AVP value set to “USAGE_REPORT” forthe corresponding session, monitoring client 10 may activate all thestored Usage-Monitoring-Information objects and begin monitoring thecorresponding session/flow. When the monitoring client 10 receives anEvent-Trigger AVP value set to “NO_EVENT_TRIGGERS” when monitoringclient 10 is doing active monitoring, monitoring client 10 may reportthe accumulated usage and cleanup all the monitoring keys.

In accordance with various techniques of this disclosure, monitoringclient 10 may transmit a usage monitoring report indicative of usage ofa service for which usage monitoring was previously activated andreceive, in response to the usage monitoring report, an indication todeactivate usage monitoring for the service in the manner describedabove. In response to the indication to deactivate the usage monitoring,monitoring client 10 may remove any monitoring keys that were configuredas a result of activating the usage monitoring.

In other words, when the PCRF deletes a usage-monitoring object inresponse to a CCR-U with Event-trigger set to “USAGE_REPORT” by sendingUSAGE_MONITORING_DISABLED with a Usage-Monitoring-Support AVP, theaction defined in monitoring client 10 is as follows:

Cleanup the monitoring keys implicitly (irrespective of whether theobject had hit threshold earlier while sending CCR-U or not).

Monitoring client 10 may not send any usage-report for these objects toPCRF.

Monitoring client 10 is doing the implicit delete because the PCRF hadreceived the report in this CCR-U only (whose CCA-U PCRF disabled usagemonitoring), so the PCRF likely does not need the report again.

In accordance with various techniques of this disclosure, monitoringclient 10 may establish a session by which a mobile device 6 is toaccess a service in the manner noted above. In response to receiving anindication to activate a charging rule having an incomplete indicationto activate usage monitoring with respect to the service provided viathe session, monitoring client 10 may reject the charging rule. In otherwords, when monitoring client 10 receives the dynamic rule from PCRF viaa Charging-Rule-Definition AVP along with a Monitoring-Key AVP butwithout the Usage-Monitoring-Information with same Monitoring-Key AVP ormonitoring client 10 had not received the Usage-Monitoring-InformationAVP earlier (through earlier RAR/CCA messages), then monitoring client10 may reject the rule. Monitoring client 10 may also send a CCR-U withCharging-Rule-Report AVP. Monitoring client 10 may reject the ruleirrespective of whether monitoring client 10 had received anEvent-Trigger AVP set to ‘USAGE_REPORT’ or not. Monitoring client 10 mayadd a new result_code in the CCR-U to indicate this error.

Moreover, when monitoring client 10 receives a Charging-Rule-Install AVPfor a predefined rule (e.g., PCRF activates a predefined rule), wherethe rule is configured with a Monitoring-Key AVP and the receivedmessage does not include the Usage-Monitoring-Information AVP with asame Monitoring-Key or the TDF had not received theUsage-Monitoring-Information AVP earlier (through earlier RAR/CCAmessages), monitoring client 10 may reject the rule. As noted above,monitoring client 10 may send a CCR-U with a Charging-Rule-Report AVP.Monitoring client 10 may reject the rule irrespective of whethermonitoring client 10 had received an Event-Trigger AVP set to‘USAGE_REPORT’ or not. Monitoring client 10 may add a new result_code inthe CCR-U to indicate this error.

While described with respect to a service provided via the session, thetechniques may be performed in instances where monitoring is enabledwith respect to the entire session (e.g., when the Monitoring-Key AVP isomitted from the CCR/CCA message exchange). That is, when usagemonitoring is activated for the entire session, the usage monitoring iseffectively enabled for each service provided via the session whetherthere is one service or a plurality of services provided via thesession. As a result, when usage monitoring is enabled for a session, itshould be understood that usage monitoring is performed for a service ofthe session. Accordingly, the techniques may be performed both whenusage monitoring is activated for a service provided via a session, oneof a plurality of services provided via the session, or the entiresession.

FIG. 2 is a block diagram illustrating an example network system 20 thatperforms the usage monitoring control techniques described in thisdisclosure. Network system 20 may represent an example instance ofnetwork system 2 of FIG. 1. Network system 20 includes a Long TermEvolution (LTE) mobile service provider network 22 (“mobile network 22”)that includes an Evolved Packet Core (EPC) interfaced to an EvolvedUTRAN (E-UTRAN) 23. Mobile network 22 enables and transports servicedata exchanged between wireless device 6 and packet data networks, suchas IP Multimedia Subsystem (IMS) network 36. IMS 36 may represent anexample of PDN 12 of FIG. 1. Mobile network 22 may represent anembodiment of mobile service provider network 4 of FIG. 1.

Mobile network 22 provides mobility management, session management, andpacket routing and transfer for network system 20. The mobile network 22EPC comprises PDN Gateway 30 (“PGW 30”) logically connected to ServingGateway 46 (“SGW 46”) via S5/S8 interface 51 operating over acommunication link. PGW 30 hosts packet filtering, lawful interception,PDP address allocation, and other functionality. PGW 30 may implement anedge router between mobile network 22 and external PDNs, e.g., IMS 36.As described in additional detail below, PGW 30 comprises Policy andCharging Enforcement Function (PCEF) 32 to perform packet gating,filtering, and charging control.

PGW 30 may represent an example instance of gateway 8 of FIG. 1. S5/S8interface 51 provides protocols to foster user plane tunneling andtunnel management between PGW 30 and SGW 46. S5/S8 interface 51 maycomprise a user plane protocol stack that includes GPRS TunnelingProtocol-User Plane (GTP-U) executing over User DatagramProtocol/Internet Protocol (UDP/IP). The term “communication link,” asused herein, comprises any form of transport medium, wired or wireless,and can include intermediate nodes such as network devices. SGW 46 hostsmobility anchoring, packet routing and forwarding, lawful interception,and other functionality.

The mobile network 22 additionally includes Mobility Management Entity44 (“MME 44”) logically connected to SGW 46 via S11 interface 45operating over a communication link. S11 interface 45 provides protocolswith which MME 44 establishes and manages bearers that traverse orterminate at SGW 46. S11 interface 45 may comprise a control planeprotocol stack that includes GTP-Control Plane (GTP-C) executing overUDP/IP. In addition to bearer management and establishment, MME 44 hostsNon-Access Stratum (NAS) signaling, PDN 30 and SGW 46 selection,roaming, and authentication, for instance. In various embodiments,mobile network 22 comprises additional MMEs, SGWs, and/or PGWs.

SGW 46 and MME 44 connect to E-UTRAN 23 via respective aspects of an S1interface. Specifically, SGW 46 logically connects to individual E-UTRAN23 via S1-U interface 47 operating over a communication link. MME 44logically connects to individual E-UTRAN 23 via S1-MME interface 43operating over a communication link to establish bearers over S1-Uinterface 47 between SGW 46 and E-UTRAN 23. E-UTRAN 23 comprises one ormore eNode Bs. E-UTRAN 23 is communicatively coupled to wireless device6 (which is an example of a mobile device) via a radio link operatingover Uu interface 55.

Wireless device 6, which represents an instance of wireless device 6 ofFIG. 1, is a User Equipment (UE) that attaches to mobile network 22 toreceive services during an attachment session identifiable by acombination of a wireless device 6 PDP address and an IMS 36 APN.Applications executing on wireless device 6 issues resource requests 40to application function 38 to initiate service sessions forcorresponding services. Resource requests 40 are application-layersignaling messages

Network 20 additionally includes IP Multimedia Subsystem 36 (“IMS 36”),an operator service that the operator of mobile network 22 may use toprovide services using, for example, the Session Initiation Protocol(SIP). In some aspects, IMS 36 represents one or more other instances ofthe services layer that provides services to devices, including wirelessdevices, attached to respective connectivity access networks, such asmobile network 22. For example, IMS 36 may represent non-IMS basedoperator services operating according to other standard or proprietaryprotocols. As another example, IMS 36 may represent services notprovided by the operator of mobile network 22 and instead provided, forinstance, via the Internet or another packet data network.

IMS 36 comprises application function 38 (“AF 38”), an IMS 36 elementthat offers applications requiring dynamic policy and/or charging withcontrol over service data traffic that traverses mobile network 22.Application function 38 is communicatively coupled to Policy Control andCharging Rules Function entity 24 (“PCRF 24”) via Rx interface 49.Application function 38 receives resource requests 40, which eachcomprise a request for a different service session, such as an IMS voicecall, from wireless device 6. Application function 38 extracts servicesession description information from resource requests 40 and providesservice session description information, such as Session DescriptionProtocol (SDP) parameters, to PCRF 24 in service session descriptionmessages 49 sent over Rx interface 49. A service session may bealternatively referred to as an AF session or application session.

PCRF 24 provides network control for mobile network 22 by way of servicedata flow (SDF) detection, QoS, gating and packet flow-based charging.PCRF 24 receives service session description information for servicesessions in service session description messages 49, calculates theproper QoS authorization, and generates new (and/or modifies existing)PCC rules that determine treatment of matching service data flows inPolicy Charging and Enforcement Function entity 32 (“PCEF 32”) and othercomponents of mobile network 22. PCRF 24 installs the new (and/ormodified) PCC rules for service sessions to PCEF 32 using PCC ruleinstallation messages sent over Gx interface 52, a reference pointbetween PCRF 24 and PCEF 32 that enables signaling of PCC rules. In thecontext of PCRF 24 generating and installing new PCC rules, these PCCrules may be referred to as “dynamic charging rules” given that PCRF 24may dynamically generate and install the PCC rules. PCC ruleinstallation messages may therefore include messages that includeCharging-Rule-Definition attribute-value pairs (AVPs) that enable PCEF32 to install the dynamic charging rules (which may also be referred toas “dynamic PCC rules”). PCRF 24 may also initiate the installation ofpredefined charging rules (which may be referred to as “predefined PCCrules”). In this respect, PCC rule installation messages may alsorepresent messages having Charging-Rule-Install AVPs.

Gx interface 52 executes a communication protocol that may comprise, forexample, Remote Authentication Dial-In User Service (RADIUS) orDiameter. PCRF 24 may be implemented within a router and, in variousembodiments, mobile network 22 may comprise multiple PCRFsinterconnected to multiple PGWs. In some instances, PCRF 24 receivesservice session information from PCEF 32, a Subscription ProfileRepository (SPR), or a Bearer Binding and Event Reporting Function(BBERF) entity in addition to, or instead of, from AF 38.

PCEF 32 is a packet management entity of PGW 30 that performs servicedata flow detection, policy enforcement and flow based charging. PCEF 32receives dynamic PCC rules determined by PCRF 24 for service sessions inPCC rule installation messages via Gx interface 52. In some instances,an operator provisions PCEF 32 with pre-defined/static PCC rules createdand configured by the operator, which PCRF 24 may install via the abovenoted Charging-Rule-Install AVP.

Upon receiving dynamic PCC rules or in response to installing predefinedPCC rules for corresponding service sessions, PCEF 24 initiatesestablishment of new bearers, or modification or utilization of existingbearers and binds the bearers to the PCC rules. As a result, PCEF 32causes PGW 30 to transport inbound packets that match service data flowtemplates of any of the PCC rules using the respective bearer to whichthe PCC rule is bound. PCEF 32 may bind multiple PCC rules to a singlebearer.

In the illustrated embodiment, PCEF 32 upon receiving PCC rules in PCCrule installation messages initiates establishment, within mobilenetwork 22, of bearer 50 for the wireless device 6 session fortransporting service data flows between wireless device 6 and IMS 36 byway of PGW 30. Bearer 50 may represent an EPS bearer or other 3GPPbearer. Charging control information in the PCC rules identify servicedata flows and specify parameters for charging control. The PCC rulepolicy and charging control information may depend on subscriptioninformation such as subscriber profiles configured within PGW 30 andassociated with subscriber sessions for the subscriber, as described infurther detail with respect to FIG. 3. PCEF 32 binds each of thereceived PCC rules generated for bearer 50 according to the policycontrol information specified within the respective PCC rules, and PCEF32 performs charging control with respect to bearer 50 service datatraffic according to charging control information included in the PCCrules and subscription information received and stored by PGW 30.

PCRF 24 may also communicate, via an Sd interface 63, with a trafficdetection function (TDF) 64 executed or otherwise performed by PGW 30.TDF 64 may perform a traffic detection function in accordance with, asone example, the 3GPP Specification 29.212 and other 3GPP Specificationnoted above. PCRF 24 may communicate Application Detection and Control(ADC) rule installation messages via the Sd interface. These ADC ruleinstallation messages may be similar and potentially substantiallysimilar to the PCC rule installation messages described above withrespect to the Gx interface 52, except that these rules may relatelayer-4 and above application detection. These ADC messages may includesimilar AVPs as the PCC rule installation messages described above butmay identify services at layer 4 and above (e.g., including layer-7application detection). As such, Sd interface 63 may, similar to the Gxinterface, execute a communication protocol that may comprise, forexample, Remote Authentication Dial-In User Service (RADIUS) orDiameter.

In accordance with various techniques of this disclosure, PGW 30 mayestablish a session, e.g., one of sessions 50, by which wireless device6 is to access a service. In response to receiving an incompleteindication to activate usage monitoring with respect to the session, PGW30 may configure the usage monitoring without activating the usagemonitoring. More specifically, as shown in the example of FIG. 2, PGW 30may include monitoring client 10. Monitoring client 10 may perform PCEF32, TDF 64, or both PCEF 32 and TDF 64, usage monitoring control inaccordance with various aspects of the techniques described in thisdisclosure. Although monitoring client 10 is shown in the example ofFIG. 2 as including both PCEF 32 and TDF 64, the techniques may beapplied with respect to a monitoring client 10 that includes only PCEF32, only TDF 64, or both PCEF 32 and TDF 64.

PGW 30 may generally establish bearer 50 with wireless device 6,invoking monitoring client 10 to establish PCC/ADC rules eitherdynamically or through installation of pre-defined PCC/ADC rules. PGW 30may also alter existing rules by, at least in part, exchanging one or aseries of messages (e.g., CCR-U/CCA-U messages that conform to theDiameter protocol), invoking monitoring client 10 to coordinate usagemonitoring of one or more services provided via the session, e.g., oneof bearers 50. Monitoring client 10 may determine various ones of thediscrepancies noted above in either activating or deactivating usagemonitoring. Monitoring client 10 may alternatively be executed by aservice control gateway (SCG), which may be logically executed withinPGW 30 or operate as a separate device or node within the network (thelatter of which is described in more detail with respect to the exampleof FIG. 7).

For example, Monitoring client 10 may determine that the mobile gatewayhas received the incomplete indication to activate the usage monitoringupon receiving a message having a Usage-Monitoring-Information AVP forsession 50 without having received, via either a previous message or themessage including the Usage-Monitoring-Information AVP, an Event-TriggerAVP with a value of “USAGE_REPORT” for the session. Upon detecting thisdiscrepancy, monitoring client 10 may configure usage monitoring (whichmay involve provisioning the various usage monitoring objects) but notactivate usage monitoring (which may involve setting the appropriateEvent-Trigger to actually enable processing of network traffic viabearer 50 to accumulate usage information). The message or messages bywhich these AVPs may be provided may include one of a credit controlrequest (CCR) message specified in accordance with a Diameter protocolor a re-auth-request (RAR) message specified in accordance with theDiameter protocol.

Monitoring client 10 may further, in response to receiving informationsufficient to complete the indication to activate the usage monitoring,activate the previously configured usage monitoring to beginaccumulating usage information for the session. As noted above, thisusage information may be on a time or data basis with respect to one ormore sessions, services, etc. Monitoring client 10 may receive, in thiscontext, the information sufficient to complete the indication toactivate the usage monitoring in the form of a message having anEvent-Trigger AVP with a value of “USAGE_REPORT” for the serviceprovided via the session. Monitoring client 10 may, upon receiving thisEvent-Trigger AVP, activate usage monitoring and thereby accumulate theusage information, which monitoring client 10 may report (e.g.,periodically or at the end of the session) to PCRF 24, online chargingserver 14 and/or offline charging server 15. Again, the messages mayinclude one of a CCR message specified in accordance with a Diameterprotocol or a RAR message specified in accordance with the Diameterprotocol.

Monitoring client 10 may further, in response to receiving an indicationto deactivate the usage monitoring for the session, report theaccumulated usage information deactivate the activated usage monitoring.In this instance, the indication to deactivate the usage monitoring mayinclude a message having an Event-Trigger attribute-value pair with avalue set to “NO_EVENT_TRIGGERS.” Again, these messages may comprise CCRor RAR messages.

In accordance with various aspects of the techniques described in thisdisclosure, monitoring client 10 may transmit a usage monitoring reportindicative of usage of a service for which usage monitoring waspreviously activated and receive, in response to the usage monitoringreport, an indication to deactivate usage monitoring for the service inthe manner described above. In response to the indication to deactivatethe usage monitoring, monitoring client 10 may remove any monitoringkeys that were configured as a result of activating the usagemonitoring.

Monitoring client 10 may transmit the usage report by, at least in part,transmitting a message with an Event-Trigger attribute-value pair havinga value set to “USAGE_REPORT” along with the usage monitoring report. Anexample of the message may include a CCR message specified in accordancewith a Diameter protocol. Monitoring client 10 may receive theindication to deactivate the usage monitoring in the form of a messagehaving a Usage-Monitoring-Support attribute-value pair with a value setto “USAGE_MONITORING_DISABLED.” The message, as one example, mayrepresent a credit control answer (CCA) message specified in accordancewith a Diameter protocol. Monitoring client 10 may remove the monitoringkey by deleting, in response to the indication to deactivate the usagemonitoring, the monitoring key without sending another usage monitoringreport. Monitoring client 10 may not send another usage report giventhat PCRF 24 elected to deactivate or otherwise discontinue monitoringin response to a previously sent usage report. Any incremental usageduring the time between sending the CCR message with the usage reportand receiving the CCA message deactivating usage monitoring may notwarrant the additional complexity of reporting usage after usagemonitoring (from the perspective of PCRF 24) has been deactivated.

In accordance with various aspects of the techniques of this disclosure,PGW 30 may establish a session by which a wireless device 6 is to accessone or more services in the manner noted above. In response to receivingan indication to activate a charging rule having an incompleteindication to activate usage monitoring with respect to a serviceprovided via the session, PGW 30 may invoke monitoring client 10, whichmay reject the charging rule. In other words, when monitoring client 10receives the dynamic rule from PCRF 24 via a Charging-Rule-DefinitionAVP along with a Monitoring-Key AVP but without theUsage-Monitoring-Information with same Monitoring-Key AVP, monitoringclient 10 may reject the rule. Likewise, when monitoring client 10 hasnot received the Usage-Monitoring-Information AVP earlier (throughearlier RAR/CCA messages), monitoring client 10 may reject the rule.Monitoring client 10 may also send a CCR-U with Charging-Rule-ReportAVP. Monitoring client 10 may reject the rule irrespective of whethermonitoring client 10 had received an Event-Trigger AVP set to‘USAGE_REPORT.’ Monitoring client 10 may add a new result_code in theCCR-U to indicate this error.

Moreover, when monitoring client 10 receives a Charging-Rule-Install AVPfor a predefined rule (e.g., PCRF activates a predefined rule), wherethe rule is configured with a Monitoring-Key AVP and the receivedmessage does not include the Usage-Monitoring-Information AVP with thesame Monitoring-Key or monitoring client 10 had not received theUsage-Monitoring-Information AVP earlier (through earlier RAR/CCAmessages), monitoring client 10 may reject the rule. As noted above,monitoring client 10 may send the CCR-U with the Charging-Rule-ReportAVP. monitoring client 10 may reject the rule irrespective of whethermonitoring client 10 had received an Event-Trigger AVP set to‘USAGE_REPORT’. Monitoring client 10 may, in this example, add a newresult_code in the CCR-U to indicate this error.

In other words, the charging rule may in some instances include adynamic charging rule. Monitoring client 10 may, in response toreceiving the indication to activate the dynamic charging rule havingthe incomplete indication to activate the usage monitoring with respectto the service provided via the session, reject the dynamic chargingrule. More specifically, monitoring client 10 may determine thatindication to activate the usage monitoring is incomplete upon receivinga message having a Charging-Rule-Definition AVP and a Monitoring-Key AVPwith a value set to a monitoring key without having received, via aprevious message or this current message, a Usage-Monitoring-InformationAVP with a value set to the same monitoring key. As a result, monitoringclient 10 may reject the dynamic charging rule.

In some instances, the charging rule may include a predefined chargingrule. Monitoring client 10 may, in response to receiving the indicationto activate the predefined charging rule having an incomplete indicationto activate the usage monitoring with respect to the service providedvia the session, reject the predefined charging rule. More specifically,monitoring client 10 may determine that the indication to activate theusage monitoring is incomplete upon receiving a message having aCharging-Rule-Install AVP with a value identifying the predefinedcharging rule without having received, via a previous message or thecurrent message, a Usage-Monitoring-Information AVP with a value set tothe same monitoring key. As a result, monitoring client 10 may rejectthe predefined charging rule.

When rejecting the charging rule, monitoring client 10 may as notedabove reject the charging rule regardless of whether an Event-Triggerattribute-value pair with a value set to “USAGE_REPORT” has beenreceived by the mobile gateway for the session. To reject the chargingrule whether dynamic or predefined, monitoring client 10 may transmit aCCR-U message with a Charging-Rule-Report AVP having a value set toindicate an error code to PCRF 24.

FIG. 3 is a block diagram illustrating an example mobile network gatewaythat performs the usage monitoring control techniques described in thisdisclosure. PGW 30 may represent an example instance of mobile networkgateway 8 of FIG. 1 or PGW 30 of FIG. 2. Control unit 70 includes one ormore processor(s) 72 that execute software instructions, such as thoseused to define a software or computer program, stored to a tangiblecomputer-readable medium (not shown in FIG. 3), such as a storage device(e.g., a disk drive, or an optical drive), or memory (such as Flashmemory, random access memory or RAM) or any other type of volatile ornon-volatile memory, that stores instructions to cause a programmableprocessor to perform the techniques described herein. Alternatively, orin addition, control unit 70 may comprise dedicated hardware, such asone or more integrated circuits, one or more Application SpecificIntegrated Circuits (ASICs), one or more Application Specific SpecialProcessors (ASSPs), one or more Field Programmable Gate Arrays (FPGAs),or any combination of one or more of the foregoing examples of dedicatedhardware.

Control unit 70 of PGW 30 provides an operating environment forsubscriber management module 82, bearer module 84, configurationinterface 86, PCEF 32 and TDF 64 (where PCEF 32 and TDF 64 may becollectively referred to as monitoring client 10). In some examples, PGW30 may not include TDF 64. Subscriber management module 82 establishesone or more subscriber sessions 74 for a mobile network served by PGW 30and manages the subscriber sessions once established. Subscribermanagement module 82 may store session data, received in control planeprotocol messages received by PGW 30 or allocated by subscribermanagement module 82, for one or more subscriber sessions 74 incorresponding session contexts (also referred to as PDP contexts).

A session context stored for a subscriber session may include, forexample, the PDP address allocated by the mobile network for thewireless device for use in sending and receiving user packets, routinginformation used by bearer module 84 in forwarding user packets such astunnel endpoint identifiers (TEIDs) and identifiers/addresses fordownstream nodes, the APN for the session, and quality of service (QoS)profiles. In some examples, functional aspects of control unit 70 areperformed by a decentralized architecture or one or more services cardsor “subscriber management service units.” As a result, PGW 30 mayachieve increased scalability to handle thousands or millions ofconcurrent communication sessions from mobile devices. Additionaldetails regarding subscriber management are found in U.S. Pat. No.8,650,279, filed Jun. 29, 2011 and entitled “MOBILE NETWORK GATEWAYHAVING DECENTRALIZED CONTROL PLANE FOR ANCHORING SUBSCRIBER SESSIONS,”which is incorporated by reference herein in its entirety.

Forwarding unit 80 represents a forwarding plane of PGW 30 and mayinclude one or more network interfaces and forwarding components forforwarding service data traffic. PGW 30 may also, in some examples,include a distributed forwarding plane. Subscriber management module 82may install forwarding information to forwarding unit 80 for processingand forwarding data traffic from the mobile devices. Forwarding unit 80,for instance, receives user packets, maps the user packets to a sessioncontext of subscriber sessions 74, and applies forwarding information toforward the user packets according to the session context data. Forexample, forwarding of downstream user packets by forwarding unit 80 fora particular subscriber session may include encapsulating the userpackets using the GPRS Tunneling Protocol (GTP) and setting thespecified downstream TEID for the session within a GTP header.Forwarding unit 80 may receive a representation of rating groups 64 andperform aspects of PCEF 32 for subscriber sessions 74 to permithigh-speed credit control. Example details on subscriber managementmodule 82 constructing subscriber-specific forwarding paths withinforwarding unit 80 can be found in U.S. patent application Ser. No.13/172,505, filed Jun. 29, 2011 and entitled “VARIABLE-BASED FORWARDINGPATH CONSTRUCTION FOR PACKET PROCESSING WITHIN A NETWORK DEVICE,” theentire contents being incorporated herein by reference.

Configuration interface 86 of control unit 70 by which a networkmanagement system, a PCRF, or in some instances an administrator, setsconfiguration information to install subscription information, staticPCC rules, and other configuration data to control the operation of PGW30 with respect to subscriber sessions 74. Configuration interface 86may include a command line interface and/or graphical user interface(CLI or GUI) or execute a device management protocol such as NETCONF orSimple Network Management Protocol (SNMP), for instance, to request andset configuration information, such as static ones of PCC rules 73A orADC rules 73B and corresponding Event-Triggers 75A or 75B. PGW 30 mayimplement configuration information using a management information base(MIB).

As noted above, a bearer established for one of subscriber sessions 74is associated with one of PCC rules 73A, one of ADC rules 73B or bothone of PCC rules 73A and ADC rules 73B. The PCC/ADC rules 73A/73B(“rules 73”) associated with the bearer is also associated with acorresponding one or more event-triggers 75A/75B (“event-triggers 75”).PGW 30 may receive install these rules 73 as a result of, as notedabove, receiving PCC/ADC rule installation messages. PGW 30 may receivefurther messages that include Event-Trigger AVPs that defineevent-triggers 75.

In accordance with various aspects of the techniques of this disclosure,PGW 30 may establish a session by which a wireless device 6 is to accessone or more services in the manner noted above. In response to receivingan indication to activate a rule having an incomplete indication toactivate usage monitoring with respect to a service provided via thesession, PGW 30 may invoke monitoring client 10, which may reject thecharging rule. In other words, when monitoring client 10 receives thedynamic rule from PCRF via a Charging-Rule-Definition AVP along with aMonitoring-Key AVP but without the Usage-Monitoring-Information with thesame Monitoring-Key AVP, monitoring client 10 may reject the rule.Likewise, when monitoring client 10 has not received theUsage-Monitoring-Information AVP earlier (through earlier RAR/CCAmessages), monitoring client 10 may reject the rule. Monitoring client10 may also send a CCR-U with Charging-Rule-Report AVP. Monitoringclient 10 may reject the rule irrespective of whether monitoring client10 had received an Event-Trigger AVP set to ‘USAGE_REPORT.’ Monitoringclient 10 may add a new result_code in the CCR-U to indicate this error.

Moreover, when monitoring client 10 receives a Charging-Rule-Install AVPfor a predefined rule (e.g., PCRF activates a predefined rule), wherethe rule is configured with a Monitoring-Key AVP and the receivedmessage does not include the Usage-Monitoring-Information AVP with thesame Monitoring-Key or the TDF had not received theUsage-Monitoring-Information AVP earlier (through earlier RAR/CCAmessages), monitoring client 10 may reject the rule. As noted above,monitoring client 10 may send the CCR-U with the Charging-Rule-ReportAVP. Monitoring client 10 may reject the rule irrespective of whethermonitoring client 10 had received an Event-Trigger AVP set to‘USAGE_REPORT’. TDF 64 may, in this example, add a new result_code inthe CCR-U to indicate this error.

In other words, one of rules 73 may in some instances include a dynamiccharging rule. Monitoring client 10 may, in response to receiving theindication to activate the dynamic charging rule having the incompleteindication to activate the usage monitoring with respect to a serviceprovided via the session, reject the dynamic one of rules 73. Morespecifically, monitoring client 10 may determine that indication toactivate the usage monitoring is incomplete upon receiving a messagehaving a Charging-Rule-Definition AVP and a Monitoring-Key AVP with avalue set to a monitoring key without having received, via a previousmessage or this current message, a Usage-Monitoring-Information AVP witha value set to the same monitoring key. As a result, monitoring client10 may reject the dynamic one of rules 73.

In some instances, the one of rules 73 may include a predefined one ofrules 73. Monitoring client 10 may, in response to receiving theindication to activate the predefined one of rules 73 having anincomplete indication to activate the usage monitoring with respect to aservice provided via the session, reject the predefined one of rule 73.More specifically, Monitoring client 10 may determine that theindication to activate the usage monitoring is incomplete upon receivinga message having a Charging-Rule-Install AVP with a value identifyingthe predefined charging rule without having received, via a previousmessage or the current message, a Usage-Monitoring-Information AVP witha value set to the same monitoring key. As a result, monitoring client10 may reject the predefined one of rules 73.

When rejecting the charging rule, monitoring client 10 may as notedabove reject the one of rules 73 regardless of whether an Event-Triggerattribute-value pair with a value set to “USAGE_REPORT” has beenreceived by the mobile gateway for the service provided via the session(and stored as one of event-triggers 75). To reject the one of rules 73whether dynamic or predefined, monitoring client 10 may transmit a CCR-Umessage with a Charging-Rule-Report AVP having a value set to indicatean error code to PCRF 24.

FIGS. 4-6 are flowcharts illustrating exemplary operation of a mobilegateway in performing various aspects of the usage monitoring controltechniques described in this disclosure. With reference to the exampleof FIG. 4, a mobile gateway, such as PGW 30 shown in the examples ofFIGS. 2 and 3, may establish a session, e.g., bearer 50, with a wirelessdevice 6. PCRF 24 may send a message (e.g., a CCA or RAR message)including a Usage-Monitoring-Information AVP for the session. PGW 30 mayreceive this message including the Usage-Monitoring-Information AVP(100), invoking monitoring client 10 to store this AVP to acorresponding one of rules 73.

Monitoring client 10 may then determine whether an Event-Trigger AVP setto “USAGE_REPORT” has been received for the service provided via thesession (e.g., either in the message that included theUsage-Monitoring-Information AVP or in a previous message and stored toevent-triggers 75) (102). When the Event-Trigger AVP has not beenreceived (“NO” 106), monitoring client 10 may configure usage monitoringfor the session but does not activate the usage monitoring for thesession, as described above (108). Monitoring client 10 may thencontinue to determine whether the Event-Trigger AVP having a value setto “USAGE_REPORT” has been received (104). In the event monitoringclient 10 determines that the Event-Trigger AVP having a value set to“USAGE_REPORT” has been received (“YES” 106), monitoring client 10 maythen determine whether usage monitoring has been previously configured(110). When usage monitoring has not been previously configured (“NO”110), monitoring client 10 may configure usage monitoring and thenactivate the usage monitoring (e.g., by actively installing theconfigured objects monitoring objects so that usage information may beaccumulated) (112, 114). When usage monitoring has been previouslyconfigured (“YES” 110), monitoring client 10 may activate the usagemonitoring by installing the objects into the forwarding plane (114).Once activated, monitoring client 10 may collect and report accumulatedusage information (116).

With reference to the example of FIG. 5, PGW 30 may establish a sessionwith wireless device 6, configure and activate usage monitoring (120) inthe manner described above with respect to the example of FIG. 4. PGW 30may, when usage monitoring is activated, invoke monitoring client 10 tocollect and report accumulated usage information to PCRF 24 (122). Inresponse to reporting this usage information, PCRF 24 may elect totransmit a message having a Usage-Monitoring-Information AVP with avalue set to “USAGE_MONITORING_DISABLED” for the session. In otherwords, PCRF 24 may elect to disable usage monitoring by notifyingmonitoring client 10 through the Usage-Monitoring-Information AVP with avalue set to “USAGE_MONITORING_DISABLED.” Monitoring client 10 mayreceive this message having a Usage-Monitoring-Information AVP with avalue set to “USAGE_MONITORING_DISABLED” for the service provided viathe session (124). Monitoring client 10 may then delete the monitoringkey associated with the service provided via the session identified bythe message (126).

With reference to the example of FIG. 6, PGW 30 may establish a sessionwith wireless device 6 in the manner described above (130). PGW 30 maynext receive a message to install a new PCC/ADC rule or activate apredefined PCC/ADC rule, again as described above (132). PGW 30 mayinvoke monitoring client 10, which may attempt to update rules 73 toinclude or otherwise install the new PCC/ADC rule (regardless of whetherdynamic or predefined). Monitoring client 10 may install this new ruleas one of rules 73 and determine whether a Usage-Monitoring-InformationAVP has been received for the session (or, in other words, whether usagemonitoring had been configured for the session) (134). When theUsage-Monitoring-Information AVP has not yet been received (“NO” 136),monitoring client 10 may reject the PCC/ADC rule in the manner describedabove (138). When the Usage-Monitoring-Information AVP has been received(“YES” 136), monitoring client 10 may configure usage monitoring for theservice provided via the session, activate the usage monitoring for theservice provided via the session and collect and report accumulatedusage information (140-144).

In some examples, monitoring client 10 may determine, similar to theexample of FIG. 4, whether the appropriate Event-Trigger AVP has beenreceived prior to activating usage monitoring and collecting andreporting accumulated usage information. In other words, while variousaspects of the techniques have been described as being performedindependently from one another, the various aspects may be performed inconjunction with one another. For example, the Event-Trigger AVP aspectsof the techniques (e.g., described with respect to FIG. 4) may beperformed with either or both of the deactivation aspects of thetechniques (e.g., described with respect to FIG. 5) and the rule-installaspects of the techniques (e.g., described with respect to FIG. 6).Likewise, the deactivation aspects of the techniques (e.g., describedwith respect to FIG. 5) may be performed with either or both of theEvent-Trigger AVP aspects of the techniques (e.g., described withrespect to FIG. 4) and the rule-install aspects of the techniques (e.g.,described with respect to FIG. 6). Furthermore, the rule-install aspectsof the techniques (e.g., described with respect to FIG. 6) may beperformed with either or both of the Event-Trigger AVP aspects of thetechniques (e.g., described with respect to FIG. 4) and the deactivationaspects of the techniques (e.g., described with respect to FIG. 5).

FIG. 7 is a block diagram illustrating another example network system150 that performs the usage monitoring control techniques described inthis disclosure. Network system 150 may represent an example instance ofnetwork system 2 of FIG. 1. Network system 150 may be similar to networksystem 20 shown in the example of FIG. 2, except that TDF 64 has beenoffloaded from PGW 30 to a dedicated service control gateway (SCG) 62.In some cases, SCG 62 may alternatively be referred to as an applicationdelivery controller (ADC), services delivery gateway (SDG), or otherdevice that performs functionality similar to that described herein, inparticular with respect to TDF 64. SCG 62 may provide service controlfunctions to facilitate establishment, configuration and monitoring withrespect to services offered by mobile access network 22. SCG 62 mayexecute TDF 64, which may perform the techniques described in thisdisclosure. Although shown as a separate network device, SCG 62 may alsobe logically executed within PGW 30 or any other network device. SCG 62may, in some instances, refer to a dedicated computing device (which maybe referred to as a “service blade”) installed in a service plane of arouter (e.g., PGW 30). The techniques should therefore not be limited inthis respect to the dedicated network device shown in the example ofFIG. 7.

Moreover, SCG 62 interfaces with PGW 30 via SGi interface 53 and alsocommunicates with IMS 36 through a dedicated SGi interface 53. SCG 62also communicates with offline charging service 15 via a Gz interface151, which is different but similar to Ga interface 57 shown in theexample of FIG. 2. SCG 62 maintains Sd interface 63 to communicate withPCRF 24 in the manner noted above.

The techniques described herein may be implemented in hardware,software, firmware, or any combination thereof. Various featuresdescribed as modules, units or components may be implemented together inan integrated logic device or separately as discrete but interoperablelogic devices or other hardware devices. In some cases, various featuresof electronic circuitry may be implemented as one or more integratedcircuit devices, such as an integrated circuit chip or chipset.

If implemented in hardware, this disclosure may be directed to anapparatus such a processor or an integrated circuit device, such as anintegrated circuit chip or chipset. Alternatively or additionally, ifimplemented in software or firmware, the techniques may be realized atleast in part by a computer-readable data storage medium comprisinginstructions that, when executed, cause a processor to perform one ormore of the methods described above. For example, the computer-readabledata storage medium may store such instructions for execution by aprocessor.

A computer-readable medium may form part of a computer program product,which may include packaging materials. A computer-readable medium maycomprise a computer data storage medium such as random access memory(RAM), read-only memory (ROM), non-volatile random access memory(NVRAM), electrically erasable programmable read-only memory (EEPROM),Flash memory, magnetic or optical data storage media, and the like. Insome examples, an article of manufacture may comprise one or morecomputer-readable storage media.

In some examples, the computer-readable storage media may comprisenon-transitory media. The term “non-transitory” may indicate that thestorage medium is not embodied in a carrier wave or a propagated signal.In certain examples, a non-transitory storage medium may store data thatcan, over time, change (e.g., in RAM or cache).

The code or instructions may be software and/or firmware executed byprocessing circuitry including one or more processors, such as one ormore digital signal processors (DSPs), general purpose microprocessors,application-specific integrated circuits (ASICs), field-programmablegate arrays (FPGAs), or other equivalent integrated or discrete logiccircuitry. Accordingly, the term “processor,” as used herein may referto any of the foregoing structure or any other structure suitable forimplementation of the techniques described herein. In addition, in someaspects, functionality described in this disclosure may be providedwithin software modules or hardware modules.

Various embodiments have been described. These and other embodiments arewithin the scope of the following examples.

What is claimed is:
 1. A method comprising: transmitting, by a mobilegateway positioned within a mobile access network, a usage monitoringreport indicative of usage by a mobile device of a service provided overa session for which usage monitoring was previously activated;receiving, by the mobile gateway and in response to transmitting theusage monitoring report, an indication to deactivate usage monitoring ofthe service for the session; and in response to the indication todeactivate the usage monitoring, removing a monitoring key that wasconfigured as a part of activating the usage monitoring of the servicefor the session.
 2. The method of claim 1, wherein transmitting theusage monitoring report comprises transmitting a message with anEvent-Trigger attribute-value pair having a value set to “USAGE_REPORT”and the usage monitoring report.
 3. The method of claim 2, wherein themessage comprises a credit control request message specified inaccordance with a Diameter protocol.
 4. The method of claim 1, whereinreceiving the indication to deactivate the usage monitoring comprisesreceiving, in response to transmitting the usage monitoring report, amessage having a Usage-Monitoring-Support attribute-value pair with avalue set to “USAGE_MONITORING_DISABLED.”
 5. The method of claim 4,wherein the message comprises a credit control answer message specifiedin accordance with a Diameter protocol.
 6. The method of claim 1,wherein removing the monitoring key comprises deleting, in response tothe indication to deactivate the usage monitoring, the monitoring keywithout sending another usage monitoring report.
 7. The method of claim1, wherein the mobile gateway comprises a router having a servicecontrol gateway that performs the usage monitoring, the mobile gatewaypositioned between an access gateway for the mobile access network and apacket data network that provides the service.
 8. A mobile gatewaycomprising: one or more processors configured to transmit a usagemonitoring report indicative of usage by a mobile device of a serviceprovided over a session for which usage monitoring was previouslyactivated; and a memory configured to store a monitoring key that wasconfigured as a result of activating the usage monitoring for theservice, wherein the one or more processors are also configured toreceive, in response to transmitting the usage monitoring report, anindication to deactivate usage monitoring of the service for thesession, and remove, in response to receiving an indication todeactivate the usage monitoring of the service for the session, themonitoring key that was configured as a part of activating the usagemonitoring of the service for the session.
 9. The mobile gateway ofclaim 8, wherein the one or more processors are configured to transmit amessage with an Event-Trigger attribute-value pair having a value set to“USAGE_REPORT” and the usage monitoring report.
 10. The mobile gatewayof claim 9, wherein the message comprises a credit control requestmessage specified in accordance with a Diameter protocol.
 11. The mobilegateway of claim 8, wherein the one or more processors are configured toreceive, in response to transmitting the usage monitoring report, amessage having a Usage-Monitoring-Support attribute-value pair with avalue set to “USAGE_MONITORING_DISABLED”.
 12. The mobile gateway ofclaim 11, wherein the message comprises a credit control answer messagespecified in accordance with a Diameter protocol.
 13. The mobile gatewayof claim 8, wherein the one or more processors are configured to delete,in response to the indication to deactivate the usage monitoring, themonitoring key without sending another usage monitoring report.
 14. Themobile gateway of claim 8, wherein the mobile gateway comprises a routerhaving a service control gateway that performs the usage monitoring, themobile gateway positioned between an access gateway for the mobileaccess network and a packet data network that provides the service. 15.A system comprising: a device that performs a policy and charging rulesfunction; a mobile device; and a mobile gateway positioned in a mobileaccess network, wherein the mobile gateway comprises: one or moreprocessors configured to transmit a usage monitoring report indicativeof usage by a mobile device of a service provided over a session forwhich usage monitoring was previously activated; and a memory configuredto store a monitoring key that was configured as a result of activatingthe usage monitoring for the service, wherein the one or more processorsare also configured to receive, in response to transmitting the usagemonitoring report, an indication to deactivate usage monitoring of theservice for the session, and remove, in response to receiving anindication to deactivate the usage monitoring of the service for thesession, the monitoring key that was configured as a part of activatingthe usage monitoring of the service for the session.
 16. The system ofclaim 15, wherein transmitting the usage monitoring report comprisestransmitting a message with an Event-Trigger attribute-value pair havinga value set to “USAGE_REPORT” and the usage monitoring report.
 17. Thesystem of claim 15, wherein receiving the indication to deactivate theusage monitoring comprises receiving, in response to transmitting theusage monitoring report, a message having a Usage-Monitoring-Supportattribute-value pair with a value set to “USAGE_MONITORING_DISABLED”.18. The system of claim 15, wherein removing the monitoring keycomprises deleting, in response to the indication to deactivate theusage monitoring, the monitoring key without sending another usagemonitoring report.
 19. The system of claim 15, wherein the mobilegateway comprises a router having a service control gateway thatperforms the usage monitoring.
 20. A non-transitory computer-readablestorage medium having stored thereon instructions that, when executed,cause one or more processors of a mobile gateway to: transmit a usagemonitoring report indicative of usage by a mobile device of a serviceprovided over a session for which usage monitoring was previouslyactivated; receive, in response to transmitting the usage monitoringreport, an indication to deactivate usage monitoring of the service forthe session; and in response to the indication to deactivate the usagemonitoring, remove a monitoring key that was configured as a part ofactivating the usage monitoring of the service for the session.